Corrosion preventing device



P 1944. E. .1. LATTNER CORROSION PREVENTING DEVICE Filed Dec.

'IN V ENTOR.

Patented Sept. 26, 1944 UNITED STATES PATENT OFFICE CORROSION PREVENTING DEVICE Emert J. Lattner, Cedar Rapids, Iowa Application December 18, 1940, Serial No. 370,637

' 2 Claims. (Cl. 204-197) This invention relates to devices for minimizing or preventing the deposition of scale, corrosion and the like on boilers, and has particular relation to means for indicating when such a device has lost its effectiveness, and for replacing the active element of such a device.

It is well known that the action of boilers causes the precipitation or calcium, lime and other materials from the water. Also chemical and electrolytic action may be set up which corrodes the exposed surfaces. It is perhaps not so well known that, if a cartridge or the like of dissimilar materials is placed within the boiler or in the hydraulic system in such a manner that water in the boiler passes around or through the cartridge, the deposition of scale and the like and the destructive effects of electrolytic and chemical action on the walls and other parts of the boiler are minimized or prevented.

It is obvious, however, that in devices of this character one of the dissimilar materials or electrodes, which would of course be the metal higher in the electro-chemical scale, will gradually become consumed-that is, the particles of one of the electrodes will combine chemically with. the water or other fluid of the boiler, and the electrode will be gradually eaten away, thus destroying the effectiveness of the device.

It is one of the main objects or my invention to provide a device in which the active electrode may be readily replaced by a new element after its efiectiveness has become destroyed.

Still another object of my invention is to provide means for signalling that the active electrode is no longer effective so that it may be replaced.

Still another object of my invention is to provide means for withdrawing the remaining parts of the active electrode and for replacing and resetting the moving parts of the signalling means.

Other and further features and objects of the invention will be more apparent to those skilled in the art upon a consideration of the accompanying drawing and following specification, wherein are disclosed several embodiments oi the invention, with the understanding, however, that such changes may be made therein as fall within the scope of the appended claims, without departing from the spirit of the invention.

In said drawing:

Figure 1 is a view, partly in elevation and partly in section, of a device constructed accordin to one embodiment of my invention.

Figure 21s a view in side elevation of a boiler to which a device such asshown in Figure 1 has been connected. and

Figure 3 is a view, partly in section and partly in elevation, of a modified form or an electrode and valve for the device shown inliigure 1.

Referring now to the drawing:

In practicing my invention I preferably employ a cylindrical cartridge such as that indicated generally at l0 and including an outer cylinder or electrode Ii and an inner electrode l2. The outer cylinder and the inner electrode are of dissimilar materials and copper is preferably employed for the outer cylinder and zinc or the like for the inner rod or pipe l2.

Of course any other suitable dissimilar metals may be employed which are sufllciently far apart on the electro chemical scale to produce an electric current in the boiler water. Furthermore, forms other than cylindrical may be employed for the electrodes.

These cylinders are preferably joined by means 01' an electrical conductor such as the cap I). They may also be Joined at the lower end as by means of the valve member I which, in this instance, is loosely received within the cylinder.

Openings are provided at the top and bottom or at the sides 01' the cylinder, as indicated at "and I8 and ii, to permit water to flow through the cylinder.

Now this cylinder, as so constructed, may be inserted within a boiler through intake or outlet openings in the boiler or, in the case of large boilers, through hand-holes or the like, but I preferably place the device outside of the boiler and connect it in such a manner that convection currents or thermo syphon action of the water into and out of the boiler causes circulation of the boiler water through the cartridge. A typical connection is illustrated in Figure 2 in conjunction with Figure 1.

The return or inlet pipe leading to the boiler 2| is indicated at 22 and the outlet pipe or main riser at 23. I preferably enclose the cartridge in a cylindrical shell 24, and water from the outlet pipe 23 passes, by reason of thermo syphon action, through pipe 26 and valve 21 into the chamber within the shell 24, in through the openings 28 of the outer shell ii, down through the space between the inner pipe l2 and the outer cylinder II, and down through the openings H in the valve body it. The water then passes through the opening in the valve seat 29 and down through the conduit 3i through valve 32 and into the intake or return'pipe 22. A flange is preferably provided on the inner wall or the cylinder t l at it to constitute a builds to cause the water to flow between the cylinders.

The outer shell i i is of a size such as will provide a fit over an enlarged portion or flange at extending below the cap i 3, and the inner electrode i2 is threaded at the upper end, as indicated at 84, and is received in a threaded opening in the cap i3. The lower end of the electrode it is threaded into a similar recess, as at 4|, in the valve body M. The valve body I4 is provided with an elongated stem, indicated at 36, for guiding the valve body as it drops downwardly when released by disintegration of the electrode l2.

The cap it is provided with an extension of the recess in which the electrode is received, which extension is indicated at 31, and a similar extension of the recess in the valve body I4 is provided at 38. A rod of any suitable material such as copper or steel or the like, indicated at 39, passes through the inner electrode i2 and its ends are received within the recesses 31 and as. Washers 4i having a loose fit on the rod 38 are provided at the opposite ends of the pipe electrode i2 and secured in place in the cap i3 and valve body it when the electrode is screwed into place. The rod has an enlarged. button-like end 42 at its lower end and is provided with a nut 43 at the upper end so that while the valve body may drop into seating engagement with the valve seat 29 by reason of disintegration of the electrode i2, it may be removed by unscrewing the cap I: and raising the cap directly vertically above the cylinder it. i The enlarged end of the rod and the nut tie the cap, the valve, and the electrode together so they may be removed as a unit.

A blow-out valve is provided at 44 so that any accumulation of material in the bottom of the cylinder may be forced out by opening the valve.

When the apparatus is in use, an electric current flows from one electrode to the other, and the negative electrode, in this case the electrode iii, will be gradually disintegrated by chemical action, When disintegration has progressed to the point where the electrode is entirely eaten away, the valve 54 will drop and the valve face at Ma will rest on the seat 29 to close the conduit 3|. As long as the electrode i2 is whole and the boiler is in operation, there is a flow of water through the cylinder M and the cylinder is warm to the touch, but when the electrode becomes eaten through, thus destroying its effectiveness, it can no longer hold up the valve i4 and the valve will drop to close the conduit 3i. When the conduit Si is closed the cylinder cools oil because it is no longer being heated by the boiler water. Thus if the boiler is operating and the cylinder is not hot to the touch, it is an indication that the electrode it! has been eaten away and should be replaced.

in order to replace the electrode ii, the cap it; may be unscrewed to remove the assembly consisting of the ca i3, the electrode ii, the remaining portions of the electrode i2, the rod 39, and the valve id. The electrode i2 may be replaced with a new electrode and the apparatus reassembled to become slain effective. At the same time the electrode Il may be cleaned and replaced if necessary.

A modified form of the invention is illustrated in Figure 3, in which a. chain 48 of copper, brass or the like is substituted for the rod I9. This form of the invention does not require the extensions of the bores within the cap and valve, which are used in the form of the invention 11- lustrated in Figure 1, for the reason that the excess chain may normally double up to permit the valve I4 to drop into seating engagement with the valve seat 29 when the negative electrode is eaten away.

Although I have described a specific embodiment of my invention, it is apparent that modifications may be made by those skilled in the art. For instance, a. temperature indicator, or any other device suitable for indicating the cessation of flow of water through the cylinder may be employed as a signalling device instead of relying on the detection of temperature differences by touching the cylinder. These and other modiflcations are within the scope of the invention and may be made without departing from the spirit and scope of my invention as set forth in the appended claims.

I claim as my invention:

1. In a device of the character described, a casing having inlet and outlet ports, a cap nernovably mounted in the top thereof, a pair 0! electrically dissimilar metal electrodes concentrlcally arranged and suspended from said cap, the outer of said electrodes being hollow and of copper, and the inner being of zinc, a valve supported by said zinc electrode and disposed vertically over the said outlet port whereby'disintegration of the said Zinc electrode due to electrolytic action between said electrodes will drop said valve member to cover said outlet port, and means extending through the said electrodes for loosely connecting said cap member and said valve member, whereby said valve member may b lifted out of the casing by the connecting means.

2. In combination with a boiler, means for treating the boiler water including a by-pass conduit through which the boiler water passes by reason of thermosyphon action, a chamber in the by-pass conduit and a water treatment device in the chamber, said water treatment device consisting of two concentrically arranged electrodes, the outer electrode being composed of copper, while the inner electrode is composed of zinc, the electrodes being connected to cause electrolytic action therebetween, and valve means normally engaged by the inner electrode of the water treatment device and adapted, upon release by reason of disintegration of the inner electrode, to close the conduit, to stop circulation of water through the by-pass, to cause lowering of the water temperature in the device to thus signal that the device has lost its effectiveness.

EIWERT J. LAII'NER. 

